diff --git a/test/integration/autolinker_spec.mjs b/test/integration/autolinker_spec.mjs
index 4492fa556..5a8321924 100644
--- a/test/integration/autolinker_spec.mjs
+++ b/test/integration/autolinker_spec.mjs
@@ -13,7 +13,15 @@
  * limitations under the License.
  */
 
-import { closePages, loadAndWait } from "./test_utils.mjs";
+import { closePages, createPromise, loadAndWait } from "./test_utils.mjs";
+
+function waitForLinkAnnotations(page) {
+  return createPromise(page, resolve => {
+    window.PDFViewerApplication.eventBus.on("linkannotationsadded", resolve, {
+      once: true,
+    });
+  });
+}
 
 describe("autolinker", function () {
   describe("bug1019475_2.pdf", function () {
@@ -38,6 +46,7 @@ describe("autolinker", function () {
     it("must appropriately add link annotations when relevant", async () => {
       await Promise.all(
         pages.map(async ([browserName, page]) => {
+          await waitForLinkAnnotations(page);
           const url = await page.$$eval(
             ".annotationLayer > .linkAnnotation > a",
             annotations => annotations.map(a => a.href)
@@ -73,6 +82,7 @@ describe("autolinker", function () {
     it("must not add links when unnecessary", async () => {
       await Promise.all(
         pages.map(async ([browserName, page]) => {
+          await waitForLinkAnnotations(page);
           const linkIds = await page.$$eval(
             ".annotationLayer > .linkAnnotation > a",
             annotations =>
@@ -106,6 +116,7 @@ describe("autolinker", function () {
     it("must not add links that overlap even if the URLs are different", async () => {
       await Promise.all(
         pages.map(async ([browserName, page]) => {
+          await waitForLinkAnnotations(page);
           const linkIds = await page.$$eval(
             ".annotationLayer > .linkAnnotation > a",
             annotations =>
@@ -121,4 +132,50 @@ describe("autolinker", function () {
       );
     });
   });
+
+  describe("PR 19470", function () {
+    let pages;
+
+    beforeAll(async () => {
+      pages = await loadAndWait(
+        "bug1019475_2.pdf",
+        ".annotationLayer",
+        null,
+        null,
+        {
+          enableAutoLinking: true,
+        }
+      );
+    });
+
+    afterAll(async () => {
+      await closePages(pages);
+    });
+
+    it("must not repeatedly add link annotations redundantly", async () => {
+      await Promise.all(
+        pages.map(async ([browserName, page]) => {
+          await waitForLinkAnnotations(page);
+          let url = await page.$$eval(
+            ".annotationLayer > .linkAnnotation > a",
+            annotations => annotations.map(a => a.href)
+          );
+          expect(url.length).withContext(`In ${browserName}`).toEqual(1);
+
+          await page.evaluate(() =>
+            window.PDFViewerApplication.pdfViewer.updateScale({
+              drawingDelay: -1,
+              scaleFactor: 2,
+            })
+          );
+          await waitForLinkAnnotations(page);
+          url = await page.$$eval(
+            ".annotationLayer > .linkAnnotation > a",
+            annotations => annotations.map(a => a.href)
+          );
+          expect(url.length).withContext(`In ${browserName}`).toEqual(1);
+        })
+      );
+    });
+  });
 });
diff --git a/test/unit/autolinker_spec.js b/test/unit/autolinker_spec.js
index 23a30446c..2d2e4d673 100644
--- a/test/unit/autolinker_spec.js
+++ b/test/unit/autolinker_spec.js
@@ -87,6 +87,9 @@ describe("autolinker", function () {
         "CAP.cap@Gmail.Com", // Keep the original case.
         "mailto:CAP.cap@Gmail.Com",
       ],
+      ["partl@mail.boku.ac.at", "mailto:partl@mail.boku.ac.at"],
+      ["Irene.Hyna@bmwf.ac.at", "mailto:Irene.Hyna@bmwf.ac.at"],
+      ["<hi@foo.bar.baz>", "mailto:hi@foo.bar.baz"],
     ]);
   });
 
@@ -140,6 +143,7 @@ describe("autolinker", function () {
         "http//[00:00:00:00:00:00", // Invalid IPv6 address.
         "http//[]", // Empty IPv6 address.
         "abc.example.com", // URL without scheme.
+        "JD?M$0QP)lKn06l1apKDC@\\qJ4B!!(5m+j.7F790m", // Not a valid email.
       ].join("\n")
     );
     expect(matches.length).toEqual(0);
diff --git a/web/annotation_layer_builder.js b/web/annotation_layer_builder.js
index 24c4668c2..ba6ad0f9b 100644
--- a/web/annotation_layer_builder.js
+++ b/web/annotation_layer_builder.js
@@ -77,6 +77,8 @@ class AnnotationLayerBuilder {
 
   #eventAbortController = null;
 
+  #linksInjected = false;
+
   /**
    * @param {AnnotationLayerBuilderOptions} options
    */
@@ -235,9 +237,10 @@ class AnnotationLayerBuilder {
         "`render` method must be called before `injectLinkAnnotations`."
       );
     }
-    if (this._cancelled) {
+    if (this._cancelled || this.#linksInjected) {
       return;
     }
+    this.#linksInjected = true;
 
     const newLinks = this.#annotations.length
       ? this.#checkInferredLinks(inferredLinks)
diff --git a/web/autolinker.js b/web/autolinker.js
index 098acb273..d3ee14c28 100644
--- a/web/autolinker.js
+++ b/web/autolinker.js
@@ -96,31 +96,37 @@ class Autolinker {
   static #regex;
 
   static findLinks(text) {
-    // Regex can be tested and verified at https://regex101.com/r/zgDwPE/1.
+    // Regex can be tested and verified at https://regex101.com/r/rXoLiT/2.
     this.#regex ??=
-      /\b(?:https?:\/\/|mailto:|www\.)(?:[[\S--\[]--\p{P}]|\/|[\p{P}--\[]+[[\S--\[]--\p{P}])+|\b[[\S--@]--\{]+@[\S--.]+\.[[\S--\[]--\p{P}]{2,}/gmv;
+      /\b(?:https?:\/\/|mailto:|www\.)(?:[\S--[\p{P}<>]]|\/|[\S--[\[\]]]+[\S--[\p{P}<>]])+|\b[\S--[@\p{Ps}\p{Pe}<>]]+@([\S--[\p{P}<>]]+(?:\.[\S--[\p{P}<>]]+)+)/gmv;
 
     const [normalizedText, diffs] = normalize(text);
     const matches = normalizedText.matchAll(this.#regex);
     const links = [];
     for (const match of matches) {
-      const raw =
-        match[0].startsWith("www.") ||
-        match[0].startsWith("mailto:") ||
-        match[0].startsWith("http://") ||
-        match[0].startsWith("https://")
-          ? match[0]
-          : `mailto:${match[0]}`;
-      const url = createValidAbsoluteUrl(raw, null, {
+      const [url, emailDomain] = match;
+      let raw;
+      if (
+        url.startsWith("www.") ||
+        url.startsWith("http://") ||
+        url.startsWith("https://")
+      ) {
+        raw = url;
+      } else if (URL.canParse(`http://${emailDomain}`)) {
+        raw = url.startsWith("mailto:") ? url : `mailto:${url}`;
+      } else {
+        continue;
+      }
+      const absoluteURL = createValidAbsoluteUrl(raw, null, {
         addDefaultProtocol: true,
       });
-      if (url) {
+      if (absoluteURL) {
         const [index, length] = getOriginalIndex(
           diffs,
           match.index,
-          match[0].length
+          url.length
         );
-        links.push({ url: url.href, index, length });
+        links.push({ url: absoluteURL.href, index, length });
       }
     }
     return links;